The vehicle was first driven onto the Claremont Jetty about 9am (11am AEST) today.
Dozens of officers, including police negotiators, the Tactical Response Group and the canine squad, were on standby as the police helicopter circled above.
The driver yelled at passersby, repeatedly revved the vehicle, and got out of the car several times to yell at police.
“He was revving the car lots, shouting out at the police, I didn’t know what he was going to do,” witness Cathy Greatrex said.
The man’s mother arrived at the scene and watched on as officers tried to convince him to surrender.
Officers had earlier laid out a stinger and used their vehicles to cut off the Jeep’s path off the jetty.
At one point he sped towards the parked police car, ramming it and shunting it backwards, damaging the front of the car.
Soon after midday (2pm AEST), the man reversed and the Jeep’s back wheel got caught off the edge of the jetty. He accelerated forward, careering into the water.
Dozens of officers who’d been on standby descended on the scene.
The driver quickly emerged from below the surface, taking refuge on the upturned vehicle before diving back into the Swan River.
Officers with guns and Tasers drawn soon had him surrounded before he was pulled from the water by the Tactical Response Group and carried to a waiting ambulance.
What prompted the standoff remained unclear but CCTV emerged of an earlier incident with the Jeep in nearby Walter Street.
“He literally just came right up, ramped up, knocked my green bin again and missed me – went down this concrete path,” resident Carina Robert said.
“I just stood here with my jaw hanging on the ground, and then he turned the corner and there were almighty screeches tearing down the road.”
The driver remained under police guard at Sir Charles Gairdner Hospital tonight. No information was revealed about the man’s condition but it was understood his injuries weren’t serious.
No charges have been laid.